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Discussion Starter · #1 ·
Growing up we didn't have much extra so I never got a sled for myself, always using a friends or borrowing for fishing. Finally happened to be in the right place & time with a trailer when came across an 89' MX 470 which looked like it was well cared for with no rust, a new track, new seat, and it starts from cold after 3-4 pumps of the primer and a couple pulls.

I have a young family so I just wanted something to get out on that lake for icefishing and once I trust it I'll take it on the trails around my area.

I was wondering if there are common problems with this generation. I'm capable of following a repair manual but I wouldn't call myself mechanically inclined enough to diagnose based on a sound or rattle. How can I check the clutch to make sure it won't fail on me, the brake disc seems sloppy but that's probably an old key that's been worn-down.

The tool kit only has the wrenches to adjust suspension, what would you recommend is the basic set. Assuming sockets, box wrenches, screwdriver, spare bulbs, vice grips, pliers, spark plugs, socket for spark plugs, extra coil?

Excited to learn, teach the kids, and bring this sled back to life.
 

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Congrats on getting a sled. These are pretty reliable sleds, but old of course so going to depend a lot on it's history. The TRA clutches are pretty trouble free. If it works well and you aren't hearing any noises it is likely fine. Fairly easy to overhaul though without special tools so something you could do later on. Sounds like you have a good handle on a tool kit. Don't forget a spare belt. The loose brake rotor is normal for this generation. Good luck!
 

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Discussion Starter · #3 ·
The TRA clutches are pretty trouble free. If it works well and you aren't hearing any noises it is likely fine. Fairly easy to overhaul though without special tools so something you could do later on.
It does sound like it has a rattle to the clutch when it idles but not sure if that's a quirk or problem yet. Is there a quick and dirty method to see if I need to dig into it?
 

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First off, make sure its tight, I have seen the bolts work loose a bit and rattle. Otherwise you can try look and see if all the plastic guide buttons are there, missing / broken ones are possible. Have seen broken arms etc as well. Heres a link that should have the info you need. If you can get the clutch off, they are not hard to check over.

http://www.vintagesnow.com/Ski-Doo_files/1989_SM.pdf
 

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I saw you bought this sled hoping to get out and do some ice fishing. Be extremely careful in doing so. This sled is a liquid cooled sled but has no radiator. In a radiator's place there are two heat exchangers above the track under the seat. These exchangers rely on snow being thrown up against them to cool the coolant to keep the engine cool. Without snow on the ice you will have virtually no cooling for the engine. You need to be sure there is adequate snow on the ice and you travel fast enough to throw the snow off the track onto the heat exchangers to provide the cooling.

This is why fan cooled sleds are the sled of choice for ice fishing.

Lynn
 

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Discussion Starter · #6 ·
I saw you bought this sled hoping to get out and do some ice fishing. Be extremely careful in doing so. This sled is a liquid cooled sled but has no radiator. In a radiator's place there are two heat exchangers above the track under the seat. These exchangers rely on snow being thrown up against them to cool the coolant to keep the engine cool. Without snow on the ice you will have virtually no cooling for the engine. You need to be sure there is adequate snow on the ice and you travel fast enough to throw the snow off the track onto the heat exchangers to provide the cooling.
This is why fan cooled sleds are the sled of choice for ice fishing.
Lynn
Interesting, could I install something to assist in cooling?
 

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Congrats on your purchase.

As far as the rattle from the clutch goes, you can get yourself a puller for it and it comes apart quite easily. Try applying slight brake pressure when you hear the noise and see if it goes away. The brake rotors on those sleds are notorious for rattling. If that's the case, you can leave it alone as long as the brakes are working; not a whole lot worth doing to make it go away.

If you want to do a good service to the sled to help in preventing failure, there are many things that you can do. Start by checking compression, looking for oil leaking from the PTO crank seal and make sure there is no play in the crankshaft when you try to move the clutch up and down. If any of these things are problematic, it's time to take a pause before sinking time and money into it.

If these things check out fine, start with checking condition of track, sliders, idler wheels and all other suspension components. With the rear of the sled in the air, shake the drive shaft to see if you have any play in the bearings.

Check the condition of your skis and carbides. The factory skins on those models would often hold water and cause the bottom of the skis to rot out. Do what you can to make sure the steering is as tight as reasonably achievable. There is always play in the tie rods but sometimes a loose nut can cause play that can be easily fixed. Check your track tension and alignment, followed by the ski alignment.

Grease every fitting you can find with low temp grease. Empty out the chaincase oil and replace with new stuff. If for some reason the chaincase has no oil in it, it will likely be the seals around the driveshaft that are leaking.

Make sure your recoil rope is in good shape. It is a common thing for them to snap and wind into the recoil when they are in poor condition. Make sure the coolant in the overflow is at the proper level. Make sure that your sled is pumping oil as well. If you're unsure, it is a good idea to mix some oil right into the tank until you confirm this. Not too rich, as this make cause you to foul out.

Make sure your carbs are spotless and well adjusted. Check the condition of the throttle cable to the oil pump; they are commonly frayed and you cant afford to wait until it fails completely. Remove your tank and give it a good cleaning. Replace any fuel lines that are questionable. A rebuild of the fuel pump is always 8 bucks well spent.

Your service and owners manual can be found at vintagesnow.com. It will cover all of this in much greater detail.
 

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Interesting, could I install something to assist in cooling?
A set of ice scratchers will do just the thing. They are installed on the slider rail of the rear suspension and throw a fine dusting of snow onto the sliders and heat exchangers. Your sled should be equipped with a temp gauge. Mine runs at 50-60 degrees C under normal conditions. These sleds like to go fast and rev high, running at low speeds often causes overheating even when there is snow so dont be afraid to wind it out a little to cool the engine down. Sleds are terrible on glare ice, the sliders will burn up quickly no matter what your cooling system is. This is why you will often see scratchers installed on fan cooled sleds as well.
 

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All the above plus check carb boots for cracks. Happy sledding!

Sent from my CLT-L04 using Tapatalk
 

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While the ice scratchers 'Might' help in cooling the sled the chances are they really won't on hard ice with little or no snow. Towing a sled with all your gear you will have to go slowly enough that the scratchers won't be very effective. Traveling at higher speeds on the ice of a frozen lake can be dangerous if you don't know exactly what is in front of you. Those pressure cracks and ice heaves are difficult to see, especially on a clear day with the bright sun and the glare it creates.

I have seen more than one ice sled or shanty upside down on a lake because someone was going too fast. You usually see this early morning when the fishermen are hustling out to get to their favorite spot. Although I do have a couple fan cooled sleds we used my son's Polaris 4 WD Sportsman 500 with chains on the rear wheels to tow our equipment out onto the ice. Among other advantages you sit higher up making it easier to see hazards. We seldom saw snowmobiles out on the ice unless they were just playing around without towing anything.

If the ice has a covering of snow you might be able to use a snowmobile for your fishing use. The key word here is 'Snow' which a snowmobile is intended to be used in. Smaller lakes and coves are most likely your best bet. Large windblown lakes not so much.

One other word of advice: Use a ridgid hitch between the snowmobile and anything you tow. Pulling a sled or shanty with a rope can be pain or even dangerous. When you stop or slow down the sled behind you will tend to either pass you or be up against the track or rear of the sled.

Lynn
 

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Water must be different in the U.S. lol, lakes and rivers are snow covered most of the time here, unless we get a big thaw/freezing rain and re-freeze. Lots of guys use liquid cooled sleds, and I never had the need for ice scratchers till I had my first Rev XP, never saw anyone put them on an old sled. We never seemed to have hyfax issues till these latest generation of sleds, slides seemed to last much longer.

Don't get me wrong, I know liquids can heat up fast under the wrong conditions, I can see the appeal of fan cooled for utility sleds for sure. Guys just generally buy whatever they can get cheap and liquids seem more plentiful.
 

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Water must be different in the U.S. lol, lakes and rivers are snow covered most of the time here, unless we get a big thaw/freezing rain and re-freeze. Lots of guys use liquid cooled sleds, and I never had the need for ice scratchers till I had my first Rev XP, never saw anyone put them on an old sled. We never seemed to have hyfax issues till these latest generation of sleds, slides seemed to last much longer.

Don't get me wrong, I know liquids can heat up fast under the wrong conditions, I can see the appeal of fan cooled for utility sleds for sure. Guys just generally buy whatever they can get cheap and liquids seem more plentiful.
I rarely see low snow conditions on the lakes here either. We just got a big dump of fluffy powder. Went out last night and couldnt get my 90 Plus above 50mph when riding the fresh stuff. Had to tape my hood vents to stop my carbs from freezing up and clutches from slipping. Got around 6 mpg when I usually get 12-13. Gotta love the Canadian snow! I guess the carbon tax is really working this year LMAO
 

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I rarely see low snow conditions on the lakes here either. We just got a big dump of fluffy powder. Went out last night and couldnt get my 90 Plus above 50mph when riding the fresh stuff. Had to tape my hood vents to stop my carbs from freezing up and clutches from slipping. Got around 6 mpg when I usually get 12-13. Gotta love the Canadian snow! I guess the carbon tax is really working this year LMAO
At least gas prices are down!
 

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Discussion Starter · #14 ·
Grease every fitting you can find with low temp grease. Empty out the chaincase oil and replace with new stuff. If for some reason the chaincase has no oil in it, it will likely be the seals around the driveshaft that are leaking.
I checked the oil level in the chaincase but it seemed sludge-y and green, probably hasn't been touched in a few seasons. I'm planning on tackling the chaincase this weekend, when I go to reapply the cover should I use some gasket maker (https://www.permatex.com/products/gasketing/optimum-gasket-makers/permatex-optimum-black-gasket-maker/)? I can't seem to find a proper gasket and I assume there should be one on there - at least according to the service manual.
 

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There's a gasket on the chaincase. If its still good as I assume it is, re-use it. If it is torn or otherwise, replace it with the correct part. Using permatex is not the thing to do on this one.

I checked the oil level in the chaincase but it seemed sludge-y and green, probably hasn't been touched in a few seasons. I'm planning on tackling the chaincase this weekend, when I go to reapply the cover should I use some gasket maker (https://www.permatex.com/products/gasketing/optimum-gasket-makers/permatex-optimum-black-gasket-maker/)? I can't seem to find a proper gasket and I assume there should be one on there - at least according to the service manual.
 

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Might be an o-ring on that cover. Should be resusable if it's not leaking. I had a safari once (one of many) that leaked no matter what. I used orange rtv sealant and let it cure before filling with oil. Worked fine.

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At least gas prices are down!
Ya they're just giving it away LOL. Prices actually aren't as bad as I thought they would be with our oil sector virtually shut down. Alberta went from 8 billion in debt in 2014 to over 70 billion today...something has to give...not looking forward to it.
 
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